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Predict the Output

Source files are here: . If you need instructions on what do with these files, try here.

Have a look at the following Die class and the associated Main.main() method that serializes the Die.

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Die class

package ex3;
 
public class Die {
    int faceValue;
 
    public Die() {
        roll();
    }
 
    public int roll() {
        int nextValue = (int) ((Math.random() * 6) + 1);
        setFaceValue(nextValue);
        return getFaceValue();
    }
 
    public int getFaceValue() {
        return faceValue;
    }
 
    public void setFaceValue(int faceValue) {
        this.faceValue = faceValue;
    }
}

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Main class

package ex3;
 
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.Closeable;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
 
public class Main {
    public static void main(String[] args) throws IOException,
            ClassNotFoundException {
        Die d = new Die();
        int faceValue = d.getFaceValue();
 
        ByteArrayOutputStream baos = serializeObject(d);
        Die retrievedDie = deserializeObject(baos);
 
        if (retrievedDie.getFaceValue() != faceValue) {
            System.out.printf("Expected %d, but found %d\n", faceValue,
                    retrievedDie.getFaceValue());
        } else {
            System.out.printf("Serialization successful\n");
        }
 
    }
 
    private static ByteArrayOutputStream serializeObject(Die d)
            throws IOException {
        ByteArrayOutputStream baos = null;
        ObjectOutputStream oos = null;
 
        try {
            baos = new ByteArrayOutputStream(1024);
            oos = new ObjectOutputStream(baos);
            oos.writeObject(d);
        } finally {
            close(oos);
            close(baos);
        }
 
        return baos;
    }
 
    private static Die deserializeObject(ByteArrayOutputStream baos)
            throws IOException, ClassNotFoundException {
        ByteArrayInputStream bais = null;
        ObjectInputStream ois = null;
 
        try {
            bais = new ByteArrayInputStream(baos.toByteArray());
            ois = new ObjectInputStream(bais);
            return (Die) ois.readObject();
 
        } finally {
            close(ois);
            close(bais);
        }
    }
 
    private static void close(Closeable os) {
        if (os != null) {
            try {
                os.close();
            } catch (IOException e) {
                // ignore e on close
            }
        }
    }
}

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Assignment: Predict the Output

Given these 2 classes, predict the output. Please do so before continuing.

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